The product…

This product is a door control system used in refrigerated buildings where doors left open can cause refrigeration plant to run more than is necessary and hence cause excessive energy consumption.

Consisting of 2 sensors, an active sensor for the door frame and a passive sensor for the door itself coupled with a wall mounted control unit in the vicinity of the doorway. When the door is left open for longer than necessary a voice warning comes from speakers in the control unit, if the door remains open the severity of the messages increases.

The project...

Paragon Design was asked to design and source all the hardware for the product, components included: -

• Control unit enclosure
• Sensor enclosures
• Sensor brackets
• Loudspeaker mounts
• Cable assemblies
• Product labels

In addition to the functional requirements of the control unit and sensor enclosures it was necessary for them to be easy to install, extremely durable, tamperproof and aesthetically pleasing.

The solution...

It was obvious that proprietary enclosures would not be suitable for either the sensor assemblies, or control unit assembly.

Working with the clients design engineers it was decided that for the sensor assemblies the PCBs would be the same dimensionally, this would make a common enclosure possible and tooling cost effective. Paragon Design then developed a 3-part injection moulded component; both tooling and parts were sourced inexpensively from a Chinese supplier identified by Paragon Design.

Because the control unit enclosure needed to be a much larger item it was not cost effective to design an injection moulded component, therefore Paragon Design followed the tried and tested route of sheet metal fabrications designing a 2 part steel painted enclosure.